1. Field of the Invention
The present invention relates to a setting tool having a housing, a stud guide located in the housing, a hopper extending sidewise of the stud guide for receiving a nail magazine, the hopper having a guide channel extending parallel to a longitudinal extent of the hopper and having two guide regions spaced from each other in a direction parallel to a setting direction of the setting tool and extending along the guide channel, a displaceable drawer arranged in the guide channel and having a scroll spring for retaining the drawer in its initial position, and a cover for closing the hopper and displaceable along the hopper between a closed position, in which the cover closes the hopper, and an open position in which the nail magazine can be inserted into the hopper, the cover having means for displacing the drawer from its initial position to its transporting position in which the drawer clears a section of the guide channel for insertion of the nail magazine.
2. Description of the Prior Act
For driving fastening elements such as, e.g., nails in hard constructional materials such as concrete, stone, steel, and the like, gas or explosive powder charge-operated setting tools are used. As upon completion of each setting process, another nail should be pushed in a bolt or stud guide, the setting tools are equipped with a hopper projecting sidewise of the stud guide and serving for receiving a strip-shaped nail magazine and guiding the same. The delivery or transporting of separate nails of the nail magazine in a direction toward the stud guide is effected by a transporting device in form of a spring-biased drawer likewise provided in the hopper.
Such a hopper is produced, e.g., by a firm HILTI AG, Shaan, Liechtenstein and which is designated X-AM72. The hopper has a guide channel extending parallel to a longitudinal extent of the hopper and having two guide regions. The guide regions are spaced from each other in a direction parallel to the setting direction and extend along the guide channel. A drawer is arranged in the guide channel and is displaceable by a scroll spring toward the stud guide. The scroll spring axle is arranged in the drawer, and the free end of the spring is secured to the hopper in a region of the hopper adjacent to the stud guide. The hopper is provided with a cover displaceable along the hopper and which, in its closed position, closes at least an end region of the hopper remote from the stud guide. Upon displacement of the cover to its open position, the drawer is also displaced into a position in which it clears a section of the guide channel, and the scroll spring is tensioned. In this position of the drawer, a strip-shaped nail magazine is inserted in the guide channel of the hopper.
An object of the present invention is to provide a setting tool with a hopper that can be easily produced, has a high ruggedness, in which the nail magazine can be inserted by both a right-hander and a left-hander, in which the cover can be displaced in its closed position with a small force, and which would provide indication to the tool user when a new nail magazine should be inserted.
This and other objects of the present invention, which will become apparent hereinafter, are achieved by providing a setting tool of the type described above and in which the drawer is displaced into its transporting against the biasing force of the scroll spring, and is formlocking connected to the hopper in the transporting position.
Due to the connection of the free end of the scroll spring to the hopper in the region of the stud guide, the scroll spring is loaded when the cover, together with the drawer, are displaced in the position corresponding to the open position of the cover and the transporting position of the drawer. Because of the formlocking or positive connection of the drawer with the hopper in the transporting position of the drawer, a very small force is necessary for displacement of the cover in the direction toward the stud guide, i.e., in its closed position.
Advantageously, for effecting a formlocking connection of the drawer to the hopper, there is provided a two-arm retaining clip associated with the hopper and opening toward the stud guide, with the arms being elastic in a direction transverse to the setting direction and transverse to the longitudinal extent of the hopper. The drawer is provided with two openings in which free ends of the two arms engage, respectively, in the transporting position of the drawer for formlocking connection the drawer with the hopper.
For obtaining a formlocking connection, e.g., two adjacent holding noses provided in the free end regions of the two arms, respectively, can be used.
Preferably, the hopper has a substantially U-shaped cross-section opening in a direction opposite the setting direction.
The U-shaped cross-section makes the hopper more rigid and permits to insert the nail magazine in the hopper in a direction parallel to the setting direction.
For guiding the nail magazine and for providing a sidewise support for the nail magazine in the hopper, the two guide regions are used each of which is formed of two spaced from each other guide surfaces. The distance between the two guide surfaces in both guide region corresponds, e.g., substantially to the diameter of the nail body. However, the distance between the two guide surfaces can be different in the two guide regions. This is, e.g., the case when separate nails of the nail magazine extend through separate guide sleeves connected with each other and guided by at least one guide region.
To prevent penetration of dirt in the hopper when the cover is in its closed position, and to provide for an easy displacement of the cover along the hopper, the hopper has, at its outer contour, in an end region remote from setting tool mouth, on its both sides, guide grooves, respectively, extending along the hopper, and the cover has guide strips projecting into the grooves for guiding the cover along the hopper. The two guide grooves are open toward the free end of the hopper. The two guide strips of the cover extend up to the end region of the cover adjacent to the stud guide.
For releasing the formlocking connection between the drawer and the hopper, the cover is provided with a pressure member for displacing the drawer, when it is located in its transporting position, in a direction toward the steel guide upon displacement of the cover from its open position into its closed position, a distance corresponding at least to a length of an opening formed in the drawer and measured in a direction transverse to the setting direction. Shortly before the cover reaches its closed position, the drawer is displaced toward the stud guide by a distance at which the formlocking connection between the drawer and the hopper is released. As a result, the loaded scroll spring can pull the drawer further toward the stud guide until the drawer adjoins the nail magazine.
For manufacturing reasons, the pressure member is provided at an end of the cover remote from the stud guide and projects from the cover in the direction toward the stud guide.
In order to provide an indication to the user when a new nail magazine need be inserted, without displacing the cover, there is provided in the hopper a viewing window. Through the window, the user can see, e.g., the position of the drawer. E.g., when the drawer becomes visible to the user, it means that a new magazine is to be inserted.
The novel features of the present invention, which are considered as characteristic for the invention, are set forth in the appended claims. The invention itself, however, both as to its construction and its mode of operation, together with additional advantages and objects thereof, will be best understood from the following detailed description of preferred embodiments, when read with reference to the accompanying drawings.